# CVE-2024-53185: smb: client: fix NULL ptr deref in crypto_aead_setkey()

> A null pointer dereference in the Linux kernel SMB client causes a crash when mounting shares with specific encryption settings.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 27 Dec 2024
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-54824, BELL-CVE-2024-53185, DEBIAN-CVE-2024-53185, GHSA-qj49-7rgr-pfmq, UBUNTU-CVE-2024-53185

## What is CVE-2024-53185?

CVE-2024-53185 is a high-severity vulnerability in Linux kernel, published on 27 Dec 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

smb: client: fix NULL ptr deref in crypto_aead_setkey()

Neither SMB3.0 or SMB3.02 supports encryption negotiate context, so
when SMB2_GLOBAL_CAP_ENCRYPTION flag is set in the negotiate response,
the client uses AES-128-CCM as the default cipher.  See MS-SMB2
3.3.5.4.

Commit b0abcd65ec54 ("smb: client: fix UAF in async decryption") added
a @server->cipher_type check to conditionally call
smb3_crypto_aead_allocate(), but that check would always be false as
@server->cipher_type is unset for SMB3.02.

Fix the following KASAN splat by setting @server->cipher_type for
SMB3.02 as well.

mount.cifs //srv/share /mnt -o vers=3.02,seal,...

BUG: KASAN: null-ptr-deref in crypto_aead_setkey+0x2c/0x130
Read of size 8 at addr 0000000000000020 by task mount.cifs/1095
CPU: 1 UID: 0 PID: 1095 Comm: mount.cifs Not tainted 6.12.0 #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-3.fc41
04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x5d/0x80
 ? crypto_aead_setkey+0x2c/0x130
 kasan_report+0xda/0x110
 ? crypto_aead_setkey+0x2c/0x130
 crypto_aead_setkey+0x2c/0x130
 crypt_message+0x258/0xec0 [cifs]
 ? __asan_memset+0x23/0x50
 ? __pfx_crypt_message+0x10/0x10 [cifs]
 ? mark_lock+0xb0/0x6a0
 ? hlock_class+0x32/0xb0
 ? mark_lock+0xb0/0x6a0
 smb3_init_transform_rq+0x352/0x3f0 [cifs]
 ? lock_acquire.part.0+0xf4/0x2a0
 smb_send_rqst+0x144/0x230 [cifs]
 ? __pfx_smb_send_rqst+0x10/0x10 [cifs]
 ? hlock_class+0x32/0xb0
 ? smb2_setup_request+0x225/0x3a0 [cifs]
 ? __pfx_cifs_compound_last_callback+0x10/0x10 [cifs]
 compound_send_recv+0x59b/0x1140 [cifs]
 ? __pfx_compound_send_recv+0x10/0x10 [cifs]
 ? __create_object+0x5e/0x90
 ? hlock_class+0x32/0xb0
 ? do_raw_spin_unlock+0x9a/0xf0
 cifs_send_recv+0x23/0x30 [cifs]
 SMB2_tcon+0x3ec/0xb30 [cifs]
 ? __pfx_SMB2_tcon+0x10/0x10 [cifs]
 ? lock_acquire.part.0+0xf4/0x2a0
 ? __pfx_lock_release+0x10/0x10
 ? do_raw_spin_trylock+0xc6/0x120
 ? lock_acquire+0x3f/0x90
 ? _get_xid+0x16/0xd0 [cifs]
 ? __pfx_SMB2_tcon+0x10/0x10 [cifs]
 ? cifs_get_smb_ses+0xcdd/0x10a0 [cifs]
 cifs_get_smb_ses+0xcdd/0x10a0 [cifs]
 ? __pfx_cifs_get_smb_ses+0x10/0x10 [cifs]
 ? cifs_get_tcp_session+0xaa0/0xca0 [cifs]
 cifs_mount_get_session+0x8a/0x210 [cifs]
 dfs_mount_share+0x1b0/0x11d0 [cifs]
 ? __pfx___lock_acquire+0x10/0x10
 ? __pfx_dfs_mount_share+0x10/0x10 [cifs]
 ? lock_acquire.part.0+0xf4/0x2a0
 ? find_held_lock+0x8a/0xa0
 ? hlock_class+0x32/0xb0
 ? lock_release+0x203/0x5d0
 cifs_mount+0xb3/0x3d0 [cifs]
 ? do_raw_spin_trylock+0xc6/0x120
 ? __pfx_cifs_mount+0x10/0x10 [cifs]
 ? lock_acquire+0x3f/0x90
 ? find_nls+0x16/0xa0
 ? smb3_update_mnt_flags+0x372/0x3b0 [cifs]
 cifs_smb3_do_mount+0x1e2/0xc80 [cifs]
 ? __pfx_vfs_parse_fs_string+0x10/0x10
 ? __pfx_cifs_smb3_do_mount+0x10/0x10 [cifs]
 smb3_get_tree+0x1bf/0x330 [cifs]
 vfs_get_tree+0x4a/0x160
 path_mount+0x3c1/0xfb0
 ? kasan_quarantine_put+0xc7/0x1d0
 ? __pfx_path_mount+0x10/0x10
 ? kmem_cache_free+0x118/0x3e0
 ? user_path_at+0x74/0xa0
 __x64_sys_mount+0x1a6/0x1e0
 ? __pfx___x64_sys_mount+0x10/0x10
 ? mark_held_locks+0x1a/0x90
 do_syscall_64+0xbb/0x1d0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Weakness: CWE-476 (NULL Pointer Dereference), CWE-416 (Use After Free)

## Which versions are affected by CVE-2024-53185?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-53185?

Apply the vendor's patch.

## Is CVE-2024-53185 being exploited?

There is no known exploitation of CVE-2024-53185 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-53185 and fix it if it is affected.

What it is: CVE-2024-53185 is a high-severity vulnerability in Linux kernel, published on 27 Dec 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-53185 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2024-53185/ (Markdown: https://insights.sbomify.com/CVE-2024-53185/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-53185
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-53185
- OSV: https://osv.dev/vulnerability/CVE-2024-53185

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-53185/
Summaries are generated and may contain mistakes; the official description above is the record.
